Electrical discharge device



June 26, R E BARCLAY ELECTRICAL DISCHARGE DEVICE Filed June l, 1931 Patented June 26, 1934 ELECTRICAL DISCHARGE DEVICE Robert E. Barclay, Chicago, Ill., assignor to Federal Electric Company, Chicago, Ill., a corporation of New York ApplcationVJune l, 1931, Serial No. 541,390

12 Claims.

My present invention relates in general to the art of creating an electron ow through an ionized gaseous path.

One of the phenomena or results accomplished by an electron flow through an ionized path is that the gaseous material forming the path is caused to glow and radiate light having color characteristics depending upon the gaseous material in which the electron flow occurs, and my invention has more particular' reference to a luminous element, the novel construction of wh'? ch provides increased utility and moreover facilitates the use of the element in illuminating systems.

My invention more particularly refers to a l5 novel lamp of the electron discharge type having several features of novelty and advantage.

Among the important objects of my invention is to provide a lamp unit of the class described adapted for operation at low voltages of the order provided in commercial or house light ing circuits. f

Another object is to provide a lighting unit or lamp of the class mentioned for detachable connection in a circuit outlet instead of requiring connections at widely spaced-apart intervals as is the case in hitherto provided devices of the class described.

Another important object is to provide a luminescent element comprising means forming an elongated closed channel, the ends of which are in adjacent relationship and connected in a socket base .whereby the element may be connected in a single outlet.

A still further object of the invention is to produce a device of the class described comprising means forming a substantially U-shaped discharge channel in which the arms of the channel are defined by a partition common to both arms.

Still another object-is to provide a devicel of the class described wherein the discharge path has portions extending-parallel and in closely spaced relationship, being, defined preferably by a single relatively thin lpartition which operates as dielectric means between the adjacent path' portions and promotes efficiency 'of operation because of the condenser action set up as a result of electrical discharge in the parallel adjacent paths adjacent intermediate dielectric, said partition being adapted also to act as heat transfer means between the paths to promote ionization of theV discharge path by applying the heat generated by the discharge for the purpose.

Another object is to provide a discharge'candle, i.e., an elongated luminescent element formed to 5 simulate the general configuration of a candle.

Numerous other objects will become apparent as the invention is more clearly understood from the following description, which, taken in connection with the accompanying drawing, discloses a preferred form of the invention.

Referring to the drawing:

Figure l is a perspective view of a multi-channel member embodying my invention;

Figure 2 is a cross-section through the member shown in Figure 1; 65

.Figure 3 is a vertical section through ,a luminescent element or `lamp formed in simulation of a candle, the lamp comprising tubing of the type shown in Figures land 2 and being provided with a temporary bombarding electrode in its upper en'd, the purpose. of which will be hereinafter more fully described;

Figure 4 is a fragmentary view, partially in section, illustrating the completed lamp -after the bombarding electrode is removed;

Figure 5 is a sectional view taken through the lower portion of the device shown in'Figures 3 and 4 for the purpose of illustrating a modification wherein a transformer is assembled in the base;

Figure 6 is a vertical section taken through a modified form of the device showing how a novel illuminating element embodying my invention may be produced by simply bending a glass tube about its mid-section to bring the electrode furnished ends in adjacent relationship in position to be mounted in a socket base whereby the element may be operated from the standard outlet socket of an electric system; and

Figure 7 is a vertical section through an adapt- 90 er base comprising a removable transformer whereby the illuminating element may be adapted for operation in electrical systemsof varying v potentials.

To illustrate my invention, I have shown on the drawing a lamp 11 comprising means 13, preferably of glass, forming a sealed envelope defining a substantially U-shaped channel 15 adapted to contain a suitable gas adapted to be electrically excited to glow, the extremities of the channel 15 100 being preferably provided with electrodes 17 by means of which to electrically excite the gas, and l the whole being mounted in a supporting base 19 providing terminal'means 21 for attaching the electrodes in a suitable electrical circuit, the base and electrodes being preferably formed to cooperate in an outlet socket of the circuit so that vthe element may be'convenientlyrrconnected in circuit.

The lamps are preferably formed of glass tubthe bore of the tubing into parallel and adjacently extending channels 27, which are separated by the vpartition 25.

The partitioned tube 23 may be made from a standard glass tube by inserting a partition in Y the tube'and fusing its edges to the wall of the tube as at 29 by fusing two tubes together laterally while plastic, or the partitioned member may be formed as a unitary integral structure as taught in my c'o-pending application, Serial Number 555,244 filed the fifth day of August 1931, which issued April 18, 1933, as United States Patent Number 1,904,348.

In order to form the lamp illustrated in Figure 4 of the drawing, a section of the partitioned member 23 of suitable length is provided at its upper end with a dome 31, which closes and forms a-connection between the upper ends of the tube channels. The lower end of each channel is provided With an electrode 17 of suitable form and is sealed inthe usual manner,A the electrodes 17 having connections extendingout through the sealed ends of the channels to permit arc producing power to be applied to the electrodes. The lower or electrode provided end of the tube is or may be set in the base 19 which is of any usual or preferred construction whereby the lamp may be connected in a power outlet socket, the 'base being formed with terminal means 21 adapted to engage and form connections with the corresponding terminals of the outlet sockets.

As illustrated in Figures 3, 4, and 5, these terminals 21 may be of bayonet type or as shown in Figure 6 they may be of the well-known screw-in type wherein one of the terminals 21 comprises a metallic shell provided with screw threads and adapted to receive the ends of the portions 13 while the other electrode comprises a stud protruding through a central opening in the base of the shell, the' parts being spaced-and secured in the shell by means of the molding compound 33.

In the .embodiments illustrated in Figures 3, 4,

and 5, the shell comprises a molded cup-shaped member adapted to receive the ends of the channel 15, said ends being embedded in the insulating compound 33 in the cup-shaped member.

.Although -I prefer to form the element of my present invention as aforesaid from tubing such as is illustrated in Figures 1 and 2 of lthe drawing, in order to accomplish advantages which`will hereinafter be more fully described, my invention is not necessarily limited to Athe particular configuration and structure of the means 13 defining the channel 15 and as shown in Figure 6 of the drawing. The part 13 may be formed by folding a tube 24 about its mid-section in order to provide parallel and adjacent arms, the ends 26 of which are arranged' in adjacent relationship, provided with electrodes, sealed and assembled in a base 19 as heretofore described in connection with the embodiment shown in Figure 4. The base 19, of course, may be the screw type shown, or any other convenient type such as the bayonet connection shown in the other figures.

If the lamp is to be used in a high voltage circuit, that is to say, a circuit-providing electricity at suiiiciently high voltage to set up and maintain the discharge arc in the lamp, the terminals 21 may be directly connected with the electrodes 17, it being understood that the terminals 21 should be sufficiently widely spacedapart in the base and insulated by the compound 33 to prevent aroma-therebetween. However, I may also operate my lamp from a low voltage source of electrical power and to this end the lamp base may be provided with a small trans- 'former 35 having a suitable-ratio and having the opposite ends of its primary winding 34 connected between the terminals 21, while the opposed ends of its secondary winding 36 are connected respectively to the `electrodes 17. The transformer 35, of course, may be formed in any suitable or convenient manner,- but I prefer to form the transformer-with so called pancake coils, that is to say, the primary and secondary windings 34 and 36 of the transformer are arranged to form fiat inter-woven coils occupying a minimum space in the base.

The exact ratio of the transformer will depend upon the available voltage in the power circuit, and the dimensions of the discharge channel 15 provided in the lamp, it being understood that the voltage necessarily applied between the terminals 17 to produce a desired brilliance in lamps of this general character has a definite ratio which varies in accordance with the length and cross-sectional area of the discharge channel so 1 that the size of the discharge path provided in the lamp and the voltage of the power supply will determine the ratio of the transformer 35.

It may also be desirable, and it is within the contemplation of my present invention, to pro- 1 vide the lamp-as a. standard element without a transformer in the base and to furnish an intermediate base as illustrated in Figure 7 of the drawing comprising means forming an enclosing socket 37, a transformer in the socket and 1 terminal means for connecting the intermediate base in a power outlet socket and for connecting the lamp in the intermediate base. The intermediate base, of course, may be provided for the bayonet connection as illustrated or may be 1 formed for screw-in connection in the Apower outlet.

The parallel channels 15 are connected at their upper ends, in the embodiment shown in Figures 3 and 4 by the dome-shaped member 31 and in 1I the embodiment illustrated-in Figure 6 by the intermediate portions of the tube 24, and forman inverted U-shaped channel. During the manufacture of devices of this general character, it is usually necessary to "bombard the channel 11 and the electrodes 17 by passing a high voltage current through the tube between the electrodes, in order to remove the impurities therein before introducing the gaseous material' which is to provide the ionized discharge path in the chan- 1;

nel. f v

Where the electrode provided ends of the discharge channel are close together, considerable difficulty is encountered in bombarding if the usual procedure is followed. The electrodes 1; 17 are so closely situated that the heat created during `bombardment frequently results in fusing the intervening glass adjacent the electrodes and thus destroying the device, since the discharge mayV pass directly through the perfora- 1. tion thus created.

In order to successfully bombard the device. I

provide a temporary bombarding electrode 41 in the upper end of the device 11 which is provided with an enlarged socket 43 for the pur- 1 pose of housing the bombarding electrode. The discharge channel 15 is then -subjected to the action of an exhaust pump in order tocreate a partial vacuum therein and high tension electrical currents are passed between the bombard- 1.

. the inner wall's'of the channel 15 to dislodge.

After the bombarding current has beenmaintainedfor a sulcient length of time, the channel may be flushed with clean dry air in order to remove the impurities and the bombarding process repeated until the channel 15 and the electrodes are thoroughly purified. The channel ,l

is then lled with a suitable gas, such as Neon, Argon, Crypton, Mercury Vapor, etc., for the p'urpose of 'providing an ionizable path for the electric discharge between the electrodes 17 through the U-shaped channel 15. The gases may be introduced into the envelope through an opening formed in the top thereof adjacent the bombarding electrode 41A and after the tube has been bombarded and filled with gas, the electrodel 4l may then be removed and the opening sealed up to form a rounded point 45 as shown in Figure 4 of the drawing and -create a sightly finish forv the element. In certain instances I may leave the bombarding electrode as a permanent part of the lamp usingv the same as a permanent cathode target While the electrodes 17 in the leg extremities function as permanent anodes. The form having three electrodes as aforesaid may be used as a rectifier or converter. The 1inished lamp has a configuration similar to that of the ordinary candle and provides an attractive and commercially, 'valuable lighting unit. If desired, the outer surface of the envelope 13 may be coated with luminescent or fluorescent material or may be 4foi-ined to provide a lightrefracting or leweled effect in accordance with the teachings of my co-pending applications, Serial Number 482,240 led the 16 day of September, 1930, and'Serial Number 482,241 filed the 16 day of September, 1930, which have issued respectively as United States Patent Number 1,873,261 on August 23, 1932, and United States Patent Number 1,904,347 on April 18, 1933.

In use, the electrical discharge extends in the U-shaped channel between the electrodes 17 so that the entire unit is illuminated above the 'base 19.

I have found that a device made in accordance withV my present invention provides a desired brilliance of illumination with less consumption of power than a similar illumination generated in discharge elements of the type heretofore provided and I believe this can be explained by the fact that the construction wherein parallel andv closelyadjacent discharge channels are separated by a common partition 25 conserves the heat generated by the discharge in the channel and the conserved heat is applied in vpromoting ionization of the gaseous medium in discharge path. In other words, a part of the heat gen.-

- erated by the discharge in both legs is transferred to the partition 25, which is heated and in turn, gives back the heat to the adjacent legs of the'dischargepath.` The element, therefore, when in operation, in and of itself heats the discharge path to a greater extent than` devices heretofore provided. This eiect depending on the spacement of the ar'ms of the discharge channel, is also present to some extent in the device illustrated in Figure 6 of the drawing. 'I'he partition 25 also operates as la dielectric extending between the arms of the U-shaped discharge path `vices having channels of equivalent .size but partiformed without the common condenser tion 25. l

-It is thought that this condenser action, in addition to the' heat effect, operates inthe described manner to promote efliciency of operation with the result that .less power is required to maintain the discharge at a desired brilliance. This eiect is also present in the device illustrated in Figure 6, but where the device is formed with an integral partition in the discharge path, the desired effect is greater.

Another feature of advantage residing in the.

structure hereinbefore described'is the production of a relatively wide luminous object without increasing the power consumption required for the illumination. The power necessary to-` varies approximately as the square of the cross` sectional area of the path. The luminous eiect produced by the device* of my inventionextends throughout the diameter of the portion 13 while pass an electrical discharge through a given path the power consumption is determined by the area of the discharge path.

I have therefore provided a lamp producinga wide streakof light with a power consumption substantially less than that provided to produceVV an equivalent streak in the devices of, this general class heretofore provided, and this advan` tage is, of course, in addition to the several other advantages apparent in my lamp and which includes its capacity to operate fromia low voltage power source, the construction wherein the lamp is carried on a base providing detachable connection in a socket outlet and the advantages derived by employing the heat conserving feature and the condenser effect of the partition 25 to promote ionizationY of the-discharge rpath."

It is thought that the invention and numerous of its attendant advantages will be understood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts Without departing from the spirit or scope of my invention or sacrificing any of its attendant advantages, the form hereinbefore described comprising preferred embodiments for the purpose of illustrating the scope of my invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is as follows:

1. A lamp unit comprising an envelope form-f ing a U-shaped channel, an electrode. in the extremity of each arm of said U-shaped channel and a bombarding electrode extending in the intermediate portions of said channel whereby each arm of theehannel may be bombarded for the purpose of removing impurities therein.

2. A lamp unit comprising an envelope. forming a U-shaped channel, an electrode in the extremity of each arm of said U-shaped channel, said arms being` separated in the envelope by a partition 'common to both arms and terminating short of one end of the envelope.

3. A discharge device comprising an envelope dening an elongated gas filled channel, spaced main electrodes in said channel, said envelope being formed so that the channel is curved intermediate the spaced electrodes, said envelope having portions izo 4 lying directly between the electrodes, wherein the envelope is provided with a temporary bombarding electrode located in the curved channel portions intermediate the main electrodes in position to discharge bombarding currents between the temporary electrode and each of the -main electrodes in order to purify each channel portion without subjecting the portions of the envelope `which lie between the main electrodes to destructive electrical strains.

4. A discharge device comprising an envelope comprising a substantially cylindrical tube sealed at its opposite ends, a partition extending from one sealed end to adjacent the other sealed end to provide within the tube a substantially U- shaped discharge channel, the arms of .which are separated by said partition, and an electrode within the channel in the extremity of each of. said arms.

5. The method of curing the gases in a dis-v charge device of the class described in which the envelope forms a curved discharge channel between the spaced electrodes of the device, which comprises applying bombarding currents in each leg of the channel by means of a temporary electrode mounted in a position common to each leg.

6. A discharge device comprising an elongated tube forming an envelope, saidtubebeingbent substantially at itsmid-point to provide a substantially U-shaped channehthe arms of which are parallel and closely adjacent one another and separated by the adjacent walls of the bent tube forming a partition between the varms of the channel, and an electrode within the channel in the extremity of each of said arms.

7. A discharge device comprising a tubular envelope comprising a glass tube, said tube being formed to provide a sealed U-shaped discharge channel having arms separated by integral parts of the envelope forming a partition means between said arms, and an electrode at the extremity of each arm of the U-shaped channel.

' 8; A discharge device comprising a tubular en- UH/velope formed tc-provide-asealed t-shaped discharge channel having arms separated by integral parts of the envelope forming partition means between said arms, an electrode at the extremity of each arm of the U-shaped channel,

a shell enclosing said electrode-provided arm` extremities and supporting said envelope. said shell being formed to t into a power outlet socket, and means on the shell for electrically connecting the electrodes with the power outlet socket.

9. A discharge device comprising a tubular envelope formed to provide a sealed U-shapeddis- .charge channel having arms separated by integral parts of the envelope forming partition means between said arms, .an electrode at the extremity of each arm of the U-shaped channel, a shell enclosing said electrode-provided arm extremities and forming a support forr the envelope, said shell being adapted to t into a poweroutlet socket, transformer means carried by said shell and connected to said electrodes and means on the shell for electrically connecting the transformer means with the power outlet socket.

l0. The combination, with a device as set forth in claim 7, including a shell enclosing said electrode-provided arm extremities and forming a support for said envelope, of adapter means comprising a support for detachably receiving said shell, transformer means on said adapter means, co-operating means on said shell and adapter means for connecting the electrodes with the transformerl means when the shell is mounted on the adapter means, said adapter means being formed for detachable and intertting connection in a power outlet socket, and means on said adapter means for electrically connecting the transformer means in the power outlet socket when the adapter means is mounted therein.

11. A discharge device comprising a tubular envelope formed to provide a sealed U-shaped discharge channel having arms separated by integral parts of the envelopeforming partition means between said arms, an electrode at the extremity of each arm of the U-shaped channel, and an electrode at the bend of the U-shaped channel;

l2. A discharge device comprising a tubular envelope formed to provide a sealed lil-shaped discharge channel having arms separated by integralparts ci the `envelope forming partition means between said arms, an electrode at the extremity of each arm of the U-shaped channel, Y 

